People are always excited to be getting in on the "ground floor" of a project as soon as (or even before) it launches. I think it's a smart idea to start building anticipation for the campaign a few days before you start (I did three days, but one week would have been better in retrospect) through your own social media. For example, an instagram or Facebook post counting down each day before the campaign. Then definitely make a big deal of the actual launch date. You will usually reach friends and family who know about your product with these types of posts and hopefully get them to pledge during the early days of the campaign. When the campaign has already begun, always try to take advantage of your milestones (1 week in, 25% of funding reached, half way through the campaign, etc.) to make announcements to your followers. Hope this helps!
My campaign has reached 72% of its $20,000 funding goal with 7 days to go.
https://www.kickstarter.com/projects/13 ... lack-dress